If we know the ration is 4:7, we know that both 4 an 7 need to be multiplied by the same exact number to equal 350. That leads us to set up the following equation:
4x + 7x = 350
We combine like terms to get:
11x = 350
We divide by 11 on both sides to get:
x= 31.82
7x represents the number of girl so :
7 * 31.82 = 222.72
Because the question says to round down, the answer is 222
